DescriptionB. chavin is characterized by having large, elevated, elongate glands on each forearm and tibia, two large, elevated, elongate glands on the outer dorsal margin of each foot and aone small, elevated gland on the outer dorsal margin of each hand. Snout-vent lengths ranged from 54.8 to 64.9 mm for females and from 47.5 to 52.0 mm for males.
Individuals exhibit considerable color variation. The dorsal and lateral ground color ranges from shades of brown to green with brown, grey, green or white spotting. The throat, chest, venter, and extremities are sulphur-yellow, cream, light brown or grey with dark brown, dark grey and white blotches and spots. The ventral surfaces of the hands and feet are olive-brown or chestnut. Some have a middorsal line.

B. chavin was collected from two cloud forest localities, at 3010 and 3017 m, from the eastern Andean slopes of central Peru. These localities are described as "bosques framentados", or naturally fragmented forests.

Life History, Abundance, Activity, and Special BehaviorsEggs are relatively large, yolky, and unpigmented. It has been suggested that breeding occurs in the rainy season, the end of August through the end of March.